California has long led the nation in advancing building energy codes, and its Title 24 standards are some of the most influential in the country. Officially known as Title 24, Part 6 of the California Building Standards Code, these regulations establish stringent requirements for the design and operation of non-residential buildings to minimize energy consumption. Since 1995, Title 24 updates have been released about every three years, each iteration becoming more stringent to reflect new technologies and sustainability goals. The most recent version, finalized in 2025, will take effect January 1, 2026.

Key Title 24 Updates for 2025

The 2025 cycle introduces significant refinements to lighting and control requirements. Among the most notable changes:

Removal of the Tailored Method: Previously, designers could use the Tailored Method to calculate lighting allowances in certain spaces. This option has been eliminated. Its wattage allowances are now included as Additional Power Allowances under the Area Category Method, simplifying compliance but tightening flexibility.

Strengthened control requirements: Rules around daylight response and occupancy sensors are stricter, ensuring that lighting turns off, dims, or reduces automatically when not needed. The threshold for daylight-responsive lighting loads has been lowered, meaning more spaces must now incorporate these controls.

Manual and multilevel control adjustments: Manual switches can be placed within the room, outside with a view, or remotely with status annunciators. Multilevel control requirements have been streamlined, generally requiring continuous dimming from 100% down to 10% unless high-intensity discharge or induction sources are used.

Outdoor lighting allowances: A new additional lighting power allowance has been introduced for outdoor spaces that utilize security cameras, acknowledging the growing importance of integrated safety systems.

Integration with other building systems: Occupancy sensors can now also serve as inputs for HVAC systems, reducing ventilation to zero during standby modes, thereby further enhancing energy efficiency.

These Title 24 updates maintain California’s reputation for pushing the envelope on energy codes while also aiming to simplify compliance pathways for designers, engineers, and building owners.

The Purpose and History of California Title 24

Title 24 was developed because California recognized early on that energy use in buildings accounted for a major share of its electricity demand and greenhouse gas emissions. Rather than relying on model codes developed nationally, the state chose to create its own framework tailored to local conditions, high energy costs, and ambitious environmental policies.

Since its inception in the mid-1970s, Title 24 has steadily evolved. In 1995, the triennial update schedule began, allowing the code to keep pace with innovations such as LED lighting, advanced controls, and integrated building systems. Each cycle tends to balance practicality, ensuring that projects can still be designed flexibly, with California’s aggressive energy efficiency and carbon reduction goals.

The 2025 update is part of this ongoing legacy. California policymakers estimate that the new standards, across all building systems, will save $4.8 billion in statewide energy costs while lowering emissions. For lighting specifically, the focus is on ensuring that controls and system design maximize energy efficiency without sacrificing safety or usability.

Why Title 24 Matters

California Title 24 shapes how buildings function, how occupants interact with their environments, and how energy resources are managed across the grid. For designers and facility managers, it ensures that lighting codes in CA are not just about efficiency but also about aligning buildings with broader sustainability and reliability goals.

By requiring sophisticated controls, such as daylight sensors, multilevel dimming, and demand-responsive lighting, the code ensures that electricity is used only when and where it is needed. This not only reduces operating costs but also extends equipment life and supports California’s transition to a lower-carbon energy system. Click here to read the full article, originally published August 26, 2025, by Inside Lighting.